Curves workbench

Post here for help on using FreeCAD's graphical user interface (GUI).
Forum rules
and Helpful information
IMPORTANT: Please click here and read this first, before asking for help

Also, be nice to others! Read the FreeCAD code of conduct!
User avatar
Vincent B
Veteran
Posts: 4711
Joined: Sun Apr 05, 2015 9:02 am
Location: La Rochelle, France

Re: Curves workbench

Post by Vincent B »

Chris_G wrote: Sun Nov 21, 2021 7:07 pm I am making a tutorial based on your mesh.
Great master piece of surface handling!
User avatar
Chris_G
Veteran
Posts: 2572
Joined: Tue Dec 31, 2013 4:10 pm
Location: France
Contact:

Re: Curves workbench

Post by Chris_G »

Vincent B wrote: Thu Nov 25, 2021 8:45 pm hi,
I'm trying to get a smooth curve between too curves. But I stuck here.
The curve must have the slope only on Z.
How to do that?
What is wrong with the blendCurve for that purpose ?
Vincent B wrote: Thu Nov 25, 2021 8:45 pmPS: I have just changed my nickname. ;)
But the shark stays !
User avatar
Vincent B
Veteran
Posts: 4711
Joined: Sun Apr 05, 2015 9:02 am
Location: La Rochelle, France

Re: Curves workbench

Post by Vincent B »

Can't use blend curve, but some extrudes. :roll:
Attachments
slope2.FCStd
(79.19 KiB) Downloaded 42 times
Gensys
Posts: 16
Joined: Wed Sep 02, 2020 5:58 pm

Re: Curves workbench

Post by Gensys »

Hello Community,

I am creating a BSplineSurface using the Gordonssurface function from Curves Workbench.
Surface_normal.PNG
Surface_normal.PNG (52.28 KiB) Viewed 2028 times
If I create my u- and v-lines as Draft.Bsplines only, the Gordonssurface is created as expected. However, if I insert a Draft.line between points 34 and 33, for example, and connect it to the BSplines via points 30-33 and 34-38 using Draft.upgrade to form a wire (new u-line) and then create the Gordonssurface, I get the error that the Gordonssurface no longer matches the specified outer contour.
Surface_mit_Linie_Fehler.PNG
Surface_mit_Linie_Fehler.PNG (54.41 KiB) Viewed 2028 times

I have no problems with this on another test object.

Pictures / files are attached. Maybe one of you knows where my error is.


Greetings


PS: Yes I have to use this outdated version but with the newest version it doesn't work either.

OS: Windows 10 (10.0)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.18.16146 (Git)
Build type: Release
Branch: (HEAD detached at 0.18.4)
Hash: 980bf9060e28555fecd9e3462f68ca74007b70f8
Python version: 3.7.3
Qt version: 5.12.5
Coin version: 4.0.0a
OCC version: 7.3.0
Locale: German/Germany (de_DE)
Attachments
Surface_normal.FCStd
(392 KiB) Downloaded 44 times
Surface_mit_Linie_und_Fehler.FCStd
(394.7 KiB) Downloaded 39 times
Test_mit_Linie_fehlerfrei.FCStd
(62.45 KiB) Downloaded 41 times
User avatar
Chris_G
Veteran
Posts: 2572
Joined: Tue Dec 31, 2013 4:10 pm
Location: France
Contact:

Re: Curves workbench

Post by Chris_G »

Hi,
I don't know why the GordonSurface tool seems to miss Point 38.
As a workaround, I managed to get a working surface by inserting a BlendCurve between each blue InterpolationCurve (but can probably be Draft.BSpline as well) and the Line Segment.
The 5 segments are then joined into a single BSpline Curve, with joinCurve tool.

If you need Points 33 and 34 to be sharp, you can lower the Continuity2 property of the BlendCurves to C0.

gordon_with_line_segment.png
gordon_with_line_segment.png (96.05 KiB) Viewed 1944 times
Attachments
Surface_with_blendcurves.FCStd
(241.43 KiB) Downloaded 38 times
User avatar
Vincent B
Veteran
Posts: 4711
Joined: Sun Apr 05, 2015 9:02 am
Location: La Rochelle, France

Re: Curves workbench

Post by Vincent B »

This sketch gives a joincurve error. :?
Attachments
JoinCurve_bug.FCStd
(6.55 KiB) Downloaded 43 times
User avatar
Chris_G
Veteran
Posts: 2572
Joined: Tue Dec 31, 2013 4:10 pm
Location: France
Contact:

Re: Curves workbench

Post by Chris_G »

How did you double the subshapes ?

Code: Select all

o1.Edges
# >>> [(<Sketcher::SketchObject>, ('Edge3', 'Edge3', 'Edge2', 'Edge2', 'Edge1', 'Edge1'))]
User avatar
Vincent B
Veteran
Posts: 4711
Joined: Sun Apr 05, 2015 9:02 am
Location: La Rochelle, France

Re: Curves workbench

Post by Vincent B »

I can't do that. :roll: just selected edge by edge.
(Curves wb re download just few minutes ago)
Attachments
Capture.JPG
Capture.JPG (60.63 KiB) Viewed 1885 times
lrpasni
Posts: 3
Joined: Mon Nov 23, 2020 2:51 am

Re: Curves workbench

Post by lrpasni »

Hello,
I'm trying to export a STEP file of a eccentric piping reducer in a pipe system for use in a CFD model. I think the BlendSolid function is the best way to model an reducer in freeCad with the continuity scales. To give a better understanding, I'm essentially trying to do what is being done in this AutoCAD youtube tutorial at time stamp of 7:25 to 7:30
https://youtu.be/Urzqrb9YLiU

My question is: What is the range of continuity scale? It appears to be from 0 to 5, as if I type in 6 it looks the same as 5.
Also, would anyone care to guess what value of continuity is close to a real piping reducers? I'm guessing 5/5.
Thanks!
Louis
User avatar
Chris_G
Veteran
Posts: 2572
Joined: Tue Dec 31, 2013 4:10 pm
Location: France
Contact:

Re: Curves workbench

Post by Chris_G »

This property is the continuity value (continuity of the derivatives) , from C0 to G5.
Post Reply